Pneumatic rotary sheet feeding mechanism



June 1957 o. p. WELSH 2,797,092

PNEUMATIC ROTARY SHEET FEEDING MECHANISM Filed June 30, 1954 2 Sheqts-Sheet 1 INVETOR.

June 25, 1957 Filed June so, 19

O. P. WELSH PNEUMATIC ROTARY SHEET FEEDING MECHANISM 2 Sheets-Sheet 2 INVENTOR.

BYQZW a/ZZIZL/ United States Patent "ice PNEUMATIC ROTARY SHEET FEEDING MECHANISM Ormonde P. Welsh, Minneapolis, Minn, assignor to Parten Machinery Company, Minneapolis, Minn, a partnership Application June 30, 1954, Serial No. 446,416

'7 Claims. (Cl. 2'71-29) The present invention relates to a novel apparatus for feeding blanks from a stack and, more particularly, to a novel apparatus for feeding envelope blanks from a stack into a high speed automatic envelope processing machine.

In feeding blanks from a stack, considerable diific ulty has been encountered in the step of separating the blank .from the stack and, as a result, two or more blanks are sometime simultaneously separated and fed to the processing machine. In addition, blank feeding apparatus heretofore known have sometimes permitted turning or twisting of the blanks as they are fed from the stack. It is obvious that whenever a plurality of blanks are simultaneously fed to the processing machine or fed in improper overlapping or twisted relationship, the processing machine will not function properly and may become jammed. It is, therefore, an object of the present invention to provide a novel apparatus capable of overcoming these difficulties by feeding blanks one at a time and at high speeds from a stack.

Another object of the present invention is to provide a novel apparatus of the type described in the preceding paragraph wherein the blanks in the stack are retained in a novel manner to facilitate separating and feeding the blanks one at a time from the stack.

A further object of the present invention is to provide a novel apparatus capable of feeding blanks from a stack at high speeds wherein the endmost blank is positively stripped from the stack to prevent simultaneous feeding of two or more blanks.

Still another object of the present invention is to provide a novel apparatus for separating and feeding blanks from a stack at relatively high speeds while restraining the blanks from twisting and turning from the desired position.

Other objects and advantages of the present invention will become apparent from the following description and accompanying drawings wherein:

Fig. l is a somewhat schematic side elevational view of an apparatus embodying the principles of this invention;

Fig. 2' is a fragmentary perspective view illustrating the novelmeans of the present invention for stripping the blank from the stack;

Fig. 3 is a fragmentary plan view taken along line 3-3 in Fig. l and illustrating in greater detail the manner in which the blanks are supported in the apparatus;

Fig. 4 is an enlarged fragmentary view similar to Fig. 1 and showing the means for separating and feeding the blanks from the stack in greater detail; and

Fig. 5 is a fragmentary cross-sectional view taken along line 5-5 in Fig. 1.

Referring now more specifically to the drawings wherein like parts are designated by the same numerals throughout the various figures, a blank feeding apparatus embodying the principles of this invention includes a pair of spaced support bars 12 and 14 for supporting a stack 16 of envelope blanks 18'. The' support bars 12 and 14 are respectively mounted. on brackets 20 and 22, which 2,797,092 Patented June 25, 1957 brackets are slidably disposed on a transverse spreader 24 of the apparatus frame 26. The brackets 20 and 22 include depending nut portions 28 and 30 which receive an adjusting screw 32 having right and left hand thread portions whereby the support bars 12 and 14 may be adjusted toward and away from each other for receiving various sizes of envelope blanks.

As shown best in Figs. 1 and 4, the blank support bars or rails are inclined at an angle from the vertical and the horizontal so that as the blanks are fed from the lower or right hand end of the stack, the remaining blanks move downwardly. Furthermore, this arrangement permits an additional supply of blanks to be added to the stack without interrupting the feeding operation. The lower endmost blank in the stack is supported by fingers 34 and 36 fixed to the ends of the support bars 12 and 14. As shown best in Figs. 3 and 5, these fingers engage opposite margins of the blank but do not support the mid portion of the blank so that the mid portion may bend or sag downwardly. It has been found that if the endmost blank is permitted to sag unduly, the separating and feeding operation is handicapped and, therefore, in accordance with one feature of the present invention, novel means is provided for supporting the mid portion of the blank. This means includes a pair of rotatable disks 38 and 40 which also have another and even more important function which is fully set forth hereinbelow.

The disks 38 and 40 are respectively fixed on shafts 42 and 44 which are rotatably journaled in bearing members 46 and 48. The supporting member 46 is mounted on and carried by the bracket 20 and the bearing member 48 is carried by the bracket 22 whereby the disks are adjustable along with the blank support bars or rails 12 and 14. The disk 38 is driven in a counterclockwise direction, as viewed in Figs. 2 and 5, and this is accomplished by operatively connecting the rotatable shaft 42 with a drive shaft it which may be driven from any suitable source of power, not shown. More particularly, a bevelled gear 52 is fixed on the shaft 50 and meshes with a bevelled gear 54 and a drive chain 56 encircles sprockets 58 and 69 fixed to the shaft 42 and bevelled gear 54 respectively. The disk 40 is driven from the sha ft 50 by similar means but this disk is rotated in a clockwise direction.

In order to separate the lower endmost blank from the stack, a pair of suction pickers 62 and 64 are provided for gripping the outer and upper margins of the envelope blank flaps 66 and 68 and pulling the upper margin of the envelope blank away from the stack. It should be noted that since the pickers grip the opposite ends of the blank, the blank will be prevented from twisting and turning as it is separated from the stack. The pickers 62 and 64 are respectively carried at the ends of suction tubes 70 and 72 which are mounted on a rock shaft 74.

The rock shaft is oscillated to move the pickers toward and away from the stack of blank-s by means of a cam arm 76 fixed thereto and carrying a cam roller 78 engageable with a rotating cam 80. The cam 80 is fixed on a rotatable shaft 32 which is driven from the drive shaft 50 through a drive chain 84 in predetermined timed relationship with the disks 3% and 46. As shown best in Figs. 2 and 5, the disks 38 and 40 are respectively provided with radial slots 86 and 88 and the oscillating movement of the pickers 6i) and 64 is timed so that they pass through the slots to grip the endmost blank and are then withdrawn to avoid interference with the disks.

Suction is intermittent-1y applied to the pickers by connecting them to suitable vacuum apparatus, not shown, through tubes 90, 92 and 94 and valve means 96. The valve means includes a fixed body member 98 closely surrounding theshaft 82 and supported on the fra'me 26 fixed on a rotatable shaft 116.

3 by a bracket 100. A suitable packing 102 is disposed within the body member to provide a substantially airtight seal between the body member and the shaft 82. The shaft 82 is provided with a transverse aperture 104 which intermittentlyregisters with passageways 166 and 108 in the body member 98 to apply suction to the pickers.

In order to feed the separated blanks, a pair of rotatable wheels 11% and 112 carrying suction grippers 114 are As shown best in Fig. 1, each of the grippers 114 is carried on the wheel by a pivotally mounted arm 118 and a fixed cam 12% is cooperable with cam followers 122 on the arms for actuating the grippers 114 outwardly from the wheel to a blank engagement position and then retracting the grippers to disengage them from the blanks. The blanks fed by the rotatable suction wheel-s 110 and 112 downwardly between a pair of feed belts 124 and 126. The belt 124 encircles a pulley 128 fixed on the shaft 116 and then passes around a large pulley 130 and suitable idler and tensioning pulleys 132, 134 and 136. The belt 1226 encircles a drive pulley 138 and idler pulleys 140 and 142 which are positioned so that portions of the belts 12dand 126 are pressed together to grip and feed envelope blanks inserted therebetwecn. The vacuum wheels 110 and 112 and the feed belts 124 and 126 are driven in timed relationship with the oscillating movement of the pickers and the rotation of the disks 3S and 40 by the above mentioned drive chain 34 which not only encircles a sprocket 144 fixed to the shaft 82 but also engages a sprocket 146 fixed on the shaft 116 and a sprocket 148 fixed on a shaft 150 supporting the pulley 138.

The operation of the novel apparatus of this invention is illustrated best in Figs. 2 and 4. The stack of envelope blanks is of course first positioned on the support bars or rails 12 or 14 and move downwardly until the lower endmost blank is stopped and supported by the fingers 34 and 36. The drive mechanism of the apparatus is then energized so that the pickers 62 and 64 advance through the slots in the rotating disks, grip the opposite ends of the lower blank and then return to the solid line position of Fig. 4. By this action, the upper portion or margin of the blank is bent away from the stack in the manner illustrated. This portion of the separation of the endmost blank from the stack may be relatively easily accomplished since the likelihood of a vacuum occurring between marginal portions of adjacent blanks is less than the likelihood of a vacuum being created between mid portions of the blanks when the endmost blank is separated from the stack. However, in order to substantially eliminate any possibility of the upper margins of adjacent blanks sticking together during this portion of the separating operation, a pair of air nozzles 152 and 154 connected to a source of air under pressure, not shown, are positioned to direct jets of air against the edges and between the marginal portions of the blanks. Furthermore, a spring biased finger 156 engages the upper edge of the endmost blank and serves to restrain succeeding blanks from being separated from the stack with the endmost blank. This finger may be supported in any suitable manner such as on a rod 158 secured to a bracket 160.

It is understood that the disks 38 and 40 are continuously rotated so that after the upper marginal portion of the endmost blank has been bent away from the stack, as shown in Fig. 4, lips 162 and 164 of the disks enter between the forwardly bent portion of the endmost blank and the stack, as shown in Figs. 2 and 4, and positively strip the blank from the stack. The endmost blank is snapped over the stop and supporting fingers 34 and 36 so that succeeding blanks may advance downwardly into engagement With these fingers. It should be noted that the stripping disks 38 and 40 at all times provide support for the mid portion of the stack of blanks whereby the blanks are prevented from bending or sagging unduly. After the endmost blank has been stripped from the stack 4 by the disks, it assumes the dotted line position shown in Fig. 4 and is gripped by one of the suction grippers 114 and fed downwardly between the belts 124 and 126, which belts advance the blank to suitable processing machinery, not shown.

From the above description it is seen that the present invention has provided a novel apparatus whereby blanks may be separated and fed one at a time from a stack at high speeds in a manner so that any possibility of adjacent blanks sticking together is substantially eliminated. More specifically, it is seen that the present appratus has provided novel means for positively stripping an endmost blank from the stack at high speeds. Moreover, the present invention has provided a novel apparatus whereby blanks may be fed rapidly from a stack while they are restrained against twisting or turning.

While the preferred embodiment of the present invention has been shown and described herein, it is obvious that many structural details may be changed without departing from the spirit and scope of the appended claims.

The invention is claimed as follows:

1. An apparatus for feeding blanks from a stack comprising means for supporting a stack of blanks, with a longitudinal axis of the stack inclined at an angle to the horizontal and the vertical, said support means including finger means projecting upwardly and overlying a lower margin of a lower endmost blank in the stack to retain said endmost blank in the stack, rotatable disk means mounted adjacent said support means and extending across said lower margin and said finger means and further supporting said endmost blank, said disk means having radial opening means therein, and means for bending an upper portion of said endmost blank away from the stack and through said radial opening means, said disk means upon rotation thereof being operable to draw the remainder of said endmost blank away from said stack and over said finger means while maintaining support for succeeding blanks in the stack.

2. An apparatus for feeding blanks from a stack comprising means for supporting a stack of blanks, oscillating suction means for gripping an endmost blank and separating a portion thereof from the stack, means for oscillating said suction means including a cam mounted on a rotatable shaft, means including a valve for intermittently connecting said suction means with a source of vacuum, said valve including a fixed body surrounding said rotatable shaft and having passageways therein and an aperture through said shaft intermittently regis-. trable with said passageways, and means insertable between said separated portion of the endmost blank and the stack for separating the remainder of the endmost blank from the stack.

3. An apparatus for feeding blanks from a stack comprising means for supporting a stack of blanks with a longitudinal axis of the stack inclined from the horizontal and the vertical, a pair of rotatable disk means, said disk means being arranged at opposite sides of said support means and having portions extending across and supporting lower portions of a lower endmost blank in the stack, each of said disk means having a radial opening therein for traversing an upper corner portion of the lower endmost blank, a pair of spaced oscillating suction means operaable in unison and in time with said disk means for movement through said radial openings to grip the upper corner portions of the lower endmost blank and bend a portion thereof away from the stack and through said radial openings, said disk means upon rotation thereof being operable to separate the remainder of said endmost blank from said stack, and means for gripping and feeding the separated blank from the stack.

4. An apparatus for feeding blanks from a stack comprising means for supporting a stack of blanks inclined from the horizontal and the vertical, a pair of spaced rigidly interconnected oscillating suction means disposed for gripping a lower endmost blank adjacent opposite and upper corner portions thereof and for separating a portion thereof from the stack, a pair of rotatable disk means disposed adjacent opposite sides of the stack and having radially extending portions for traversing said blank corner portions and supporting mid-portions of the lower endmost blank, said disk means having radial slots therein adapted to align with said blank corner portions upon rotation of the disk means, and means for actuating said suction means and said disk means in timed relationship so that the suction means pass through the slots for gripping and partially separating the lower endmost blank from the stack and said disk means portions are inserted between the separated blank portion and the stack to separate the remainder of said lower endmost blank from the stack while continuously supporting the remainder of the blanks.

5. An apparatus as defined in claim 4 wherein said means for supporting the stack includes upstanding rigid finger means between the stack and said disk means and projecting across a lower margin of said lower endmost blank, and wherein said disk means radially extending portions traverse said finger means so as to positively snap the lower endmost blank over the finger means during a separating operation.

6. An apparatus, as defined in claim 4, which includes a pair of axially spaced suction wheels disposed adjacent to and respectively in alignment with radially extending portions of said pair of disk means for gn'pping a separated blank at laterally spaced areas and feeding the blank.

7. An apparatus, as defined in claim 6, which includes blank feed belt means for receiving the blanks from said suction wheels, said feed belt means being centered with respect to said stack and disposed between said suction wheels.

References Cited in the file of this patent UNITED STATES PATENTS 1,153,295 Dunnebier et a1. Sept. 14, 1915 1,682,276 Hartman Aug. 28, 1928 1,794,198 Murray Feb. 24, 1931 1,893,778 Klemm Jan. 10, 1933 2,011,464 Winkler et al. Aug. 13, 1935 2,315,646 Novick Apr. 6, 1943 2,686,052 Winkler et al. Aug. 10, 1954 

